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Ravensdale Water Supply

What EPA’s and Washington’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
389 people
Connections
31
Water source
Surface water bought from another system
Based in
Renton, WA
County
King
Owner
Private
The ZIP code it serves

98051

The short answer

Nothing in EPA’s and Washington’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Total trihalomethanes (TTHM) and haloacetic acids (HAA5): Washington’s own results, samples taken from June 24, 2021 to June 12, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits2

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

25.7ppb

Highest yearly average, 2021 to 2026

Averaged by year, the highest was 25.7 ppb, in 2026, below EPA’s legal limit of 80 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 25.4 ppb, in 2014.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

7.2ppb

Highest yearly average, 2021 to 2026

Averaged by year, the highest was 7.2 ppb, in 2026, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 33.3 ppb, in 2012.

What handles it

No certification claim covers this compound yet.

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

Violations since 2016

No health-based violations on file with EPA since 2016. There are 2 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are Washington’s own from 2021 on, with EPA’s national file for 2012 to 2019. Ravensdale Water Supply’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Washington’s results run from June 24, 2021 to June 12, 2026.

Testing your own tap

Ravensdale Water Supply’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Washington certifies.

The 3 labs Washington certifies closest to the area Ravensdale Water Supply serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Aqua Test, Incorporated

    Maple Valley, WA · about 6 miles

    Certified for bacteria, nitrate

    (425) 432-9360

  • AmTest Laboratories

    Renton, WA · about 18 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, disinfection byproducts

    (425) 885-1664

  • Analytical Resources, LLC

    Tukwila, WA · about 22 miles

    Certified for nitrate, lead and copper, metals, minerals and other inorganics

    (206) 695-6200

All 84 certified labs for Washington

Sources

PWSID WA5371400. Rebuilt from EPA data on Oct. 18, 2026.

Also in King County

All Washington utilities

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